Once you have figured out how many calories is required to maintain your weight, you need to eat roughly 15 to 20% more than this to gain weight and build muscle.

Eat more than this percentage (i.e. more than 25% of your TDEE) you risk gaining more of fat, and eat less ( less than your TDEE ) you will not gain muscle.

To get your macros (carbs, protein and fat) right, is a hit and trial process and you will get better with time.

Now, calorie counting is a rather tedious process, instead do the following things:

1) Note that we all eat very limited variety of meals. For example, I have been eating eggs in my breakfast, for over a decade now, and I am still not bored!

Anyways my point being our ingredients list is very limited and once you start “googling” their caloric values and maintain a dairy for the same. Over time, you will have a pretty clear idea of how much calories you are consuming.

2) Eat slowly. It takes our brain 15 minutes to figure out whether we are full or not. so once you are full, eat slightly more. Only slightly.

4) Postworkout: A big glass of banana shake, add more fruits like strawberries etc if you like. Add a little bit of chocolate syrup, this works wonder for me, as it satisfies my sweet cravings and helps me to stay away from donuts, pastries etc.

To get more protein eat yogurt, paneer (cottage cheese) with your meals. It ok to eat 3 meals a day ( eating smaller meals a day is purely a myth and its not superior to eating lesser meals )

Include lot of green vegetables ( in the form of salads mainly ), as micronutrients in them aids in the chemical processes in the body which helps build muscles.